import re
from lxml import etree

data = '<li><a href="https://www.docker.com/products/docker-datacenter">Docker Datacenter</a></li>'
searchObj = re.search('href=\"*\"', data)

pattern = re.compile(r'(href=\"*\")', re.I | re.S)  # 查找数字
result1 = pattern.findall(data)
print(result1)
